Flat valve for hydraulic machine



May 5, 1964 Filed Jan. 14, 1963 R. G. LA BORDE 2 Sheets-Sheet 1 Fig.l

Russell G. LaBor'de INVENTOR ATTORNEY May 5, 1964 R. G. LA BORDE FLATVALVE FOR HYDRAULIC MACHINE 2 Sheets-Sheet 2 Filed Jan. 14, 1963 RussellG. La Borde- INVENTOR 7 AT OYRNEY- United States Patent 3,131,605 FLATVALVE FOR HYDRAULIC MACHINE Russell G. La Borde, Milwaukee, Wis,assignor to The Oilgear Company, Milwaukee, Wis. Filed Jan. 14, 1963,Ser. No. 251,187 4 Claims. (Cl. 91-198) This invention relates to rotaryhydrodynamic machines in which pistons and cylinders are arranged in 2.cylinder barrel and the pistons reciprocate as the cylinder barrelrotates. The flow of liquid to and from the cylinders is controlled by afloating flat valve that has a pair of arcuate ports with which thecylinder ports alternately register. More particularly, the inventionrelates to the energization and de-energization of auxiliary hold-upmotors provided in bridges of the valve.

The hydrodynamic machine has a rotary cylinder barrel, and fluid flow toand from the cylinder ports therein is valved by a non-rotatable andaxial floating type of flat valve in the manner illustrated in US.Patents 2,406,138 and 3,037,489 assigned to the assignee of thisapplication.

The arrangement of the hold-up motors and of the auxiliary hold-upmotors, as is well known, is such as to make the summation of the forcemoments on the flat valve equal to zero for limit conditions of pressurefield distribution. Thus, when the pressure field is a minimum, balanceis provided by the hold-up motors, and when the pressure field is amaximum, such balance is obtained by both the hold-up and auxiliaryhold-up motors. It has been found advantageous to obtain such balance ofmoments by simultaneously energizing auxiliary hold-up motors under bothbridges of the flat valve.

The present invention is well suited for operation of the motor at slowspeed as well as at higher speeds. The auxiliary holdsup motors aresimultaneously energized whenever a greater number of cylinder portsregister with the valve pressure port and are simultaneouslyde-energized whenever a greater number of cylinder ports register withthe valve exhaust port.

According to the present invention and an object thereof, the auxiliaryhold-up motors under both bridges of the flat valve are energized andmaintained energized when an even number of cylinder ports are incommunication with the pressure port of the flat valve and theseauxiliary hold-up motors under both bridges are deenergized andmaintained de-energized when an odd number of cylinder ports are incommunication with the pressure port of the flat valve, when the totalnumber of cylinder ports is odd.

Another object of the invention is to provide a floating type valve withperipheral passage means for interconnecting the auxiliary hold-upmotors under both the bridges of the flat valve. Such means ofinterconnecting the auxiliary hold-up motors is economical to provideand is the only practical means of providing such interconnection in astud mounted flat valve where the valve is small or relatively small forthe number of hold-up motors that are provided.

Other objects and advantages of the invention will be apparent onreading the following description with the accompanying drawings, inwhich:

FIG. 1 is a view in elevation and partially in section of a hydraulicmotor embodying the present invention;

FIG. 2 is a view taken on line 2-2 of FIG. 1 to show the operating faceof the flat valve with the relative position of opposing cylinder postsindicated thereon;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2 and alsoshowing part of the support structure for the flat valve;

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FIG. 4 is a sectional view taken along the line 4-4 of FIG. 2;

FIGS. 5 and 6 are similar views of the valve plate shown in FIG. 2 butwith the opposing cylinder ports indicated in diflerent rotativepositions of distribution thereon; and FIG. 7 is a sectional view ofanother embodiment of the flat valve corresponding to the arrangementshown in FIG. 4.

The machine embodying the improved flat valve construction may be avariable displacement pump or motor having a rotatable cylinder barrelwith radially or axially arranged pistons. As shown in FIG. 1, thismachine is a fixed displacement axial piston motor 10.

A shaft adapted for coupling to a load device has a drive flange .13mounted for rotation with the shaft in section 11 of the casing. Theshaft 12 and the flange 13 are suitably rotatably supported on radialand thrust bearings, not shown, in casing section 11.

A cylinder barrel 14 is rotatably supported on axially spaced bearings16, 17 disposed on an axially extending stud 18 in the end head 19 ofthe casing section 21. The bearings 16, 17 hold the cylinder barrelagainst axial and radial displacement. The axes of shaft 12 and ofcylinder barrel 14 are inclined relative to each other to provide thefixed displacement for the motor. The cylinder barrel '14 is providedwith a plurality of cylinders 22 parallel with its axis and has axiallyreciprocable pistons 23 therein. The pistons 23 are connected to thedrive flange 13 by piston rods 24 whose ends are held in ball sockets inthe drive flange 13. The cylinder barrel is provided with an odd numberof N cylinders herein shown with nine cylinders. The shaft is linked tothe cylinder barrel by a constant velocity coupling 26 such as a Cardanshaft which couples a pair of universal joints in the axis of the shaftand in the axis of the cylinder barrel.

The cylinders 22. provide N cylinder ports 29 in the end face of thecylinder barrel and each alternately registers with a supply port 31 andan exhaust port 32 of a flat valve 33 as the cylinder barrel rotates.The ports 31, 32 are diametrically arranged arcuate slots in the frontor cylinder opposing the face of the flat valve. Axial passages in theflat valve extend through hollow pistons 45 of hold-up motors 42. andconnect port 31 with axial passages 35 in the head '19 and these joincommon manifold passage .36 which terminates in an outer connection 37which may be either a supply or discharge connection for the motor.

Axial passages in the flat valve extend through hollow pistons 45 ofhold-up motors 43 and connect port 32 to aligned axial passages 39 inend head 19 which join a common manifold passage 49 that terminates inthe other outer connection 41. Fluid supply entering outer connection 37flows through manifold passage 36, thence through axial passages 35 andaligned passages in the flat valve to its relatively high pressure orsupply port 31. Cylinder ports registering with valve supply port 31receive pressure fluid therefrom to displace their pistons. Cylinderports registering with the relatively low pressure or discharge port 32of the valve discharge their fluid thereto which fluid flows throughaxial passages in the flat valve and aligned axial passages 39 in endhead 19 to manifold passage '40 and to discharge connection.

The flat valve '38 is annular and is disposed coaxially of the stubshaft .18 and of the cylinder barrel. The flat valve is secured on theend head against rotation and for freedom of axial movement. The fiatvalve is hydraulically balanced between the cylinder barrel and the endhead by a hold-up system which produces hold-up forces acting betweenthe cylinder barrel and the flat valve.

The hold-up system comprises hold-up motors 42,, 43 and auxiliary motors47, 48 located in the bridges of the valve which are the portionsbetween the arcuate ports 31, 32. The hold-up motors 42, 43 comprisecylinders 44 always connected to their respective ports 31, 52, and havehollow pistons 45 for connecting the valve ports to the end headpassages.

Springs 46 urge the pistons -45 in seating engagement with the alignedpassages 35, 39 in the end head. The hold-up motors 42 are arrangedrelative to their associated valve port 31 to provide a hold-up forceequal and opposite the separating force developed when an odd number, /2of (N l), cylinder ports register with and are evenly distributed onvalve port 31. Hold up motors 43 are similarly arranged relative tovalve port 32 as hold-up motors 42 to valve port 31. The centroid of thehold-up force due to hold-up motors 42 lies on a transverse axis whichlies on a horizontal diametrical line bisecting the ports 31, 32, FIG.2.

According to this hold up system, the hold-up forces applied by thehold-up motors 42 or 43 are sufficient to hold the valve balancedagainst the separating force developed when four cylinder ports registerwith the supply port of the valve but are insufiicient to preventseparation when five cylinder ports register with the supply port. Inthis manner an excessive hold-up force is not applied when four cylinderports register with the pressure port and wear between the cylinderbarrel or a wear plate 36 thereon and the valve is avoided.

The auxiliary hold-up motors 47, 48 provide additional hold-up forceonly when five cylinder ports, /z(N +1), cylinder ports, communicatewith the pressure port of the valve. Auxiliary hold-up motors 47 and 48comprise cylinders 49, 50 formed in the rear face of the flat valve,FIG. 4, each having a solid or closed end bridge piston 51 therein urgedby fluid under pressure against the face of end head 19. The face of thebridges are provided with drilled passages 53, 54 to cylinder 49 andcylinder 56, respectively.

The face of the flat valve and different relative positions of cylinderports thereon are shown in FIGS. 5 and 6. Valve port 31 has portextensions 31a and 31b and valve port 32 has port extensions 32:: and3211. These port extensions are provided by tapered slots whose adjacentends are spaced apart an amount corresponding to the circumferentiallength along the flat valve of a cylinder port, and when the machine isa motor, such spacing is sli htly greater than the circumferentiallength of a cylinder port, so that a cylinder port crossing the bridgedoes not interconnect the valve ports.

When a cylinder port is centered on a bridge segment of the fiat valve,it is in registration with a hole 53 or 5-;- connecting a bridgecylinder to the face of the bridge segment. FIGS. 5 and 6 showsequential positions of the nine cylinder ports 215 to 291' inclusive,on the fiat valve. For clockwise rotation of the cylinder barrel,cylinder port 290 is leaving a bridge in FIG. 5 but is still incommunication via hole 54 with a bridge motor or auxiliary hold-up motor43 and is also now in communication with the port extension 31a. ofpressure port 31. On the diametrically opposite bridge we see cylinderport 2292 beginning to cross the bridge and is not yet in communicationwith. auxiliary hold-up motor 47 but is still in communication withpressure port 31 through its portion extension 33b. Thus, five of thenine cylinder ports are in communication with pressure port 31.Auxiliary hold-up motor 48 is thus energized by pressure fluid conductedfrom pressure port 31 by means of the overlying cylinder port 29a.

Slightly further rotation of the cylinder barrel, as illustrated in FIG.6, shows cylinder port 29a having moved out of registration with hole 54to auxiliary hold-up motor Such rotation has also brought cylinder port2% into registration with bridge hole 53 while cylinder port 2% is stillin communication with pressure port 31 through port extension 31b. Thus,auxiliary hold-up motor 47 is energized by pressure fiuid conducted bymeans of overlying cylinder port 2%. Continued rotation, not shown, willcenter cylinder port 29c on the bridge and out of registration witheither port 31 or 32, and thereafter begin registration of cylinder port29c with exhaust port 32 via port extension 32a while cylinder port 291'begins to cross the opposite bridge. Thus, one auxiliary hold-up motor47 is sequentially energized and de-energized by each cylinder portcrossing its associated bridge and the other auxiliary hold-up motor 48is sequentially de-energized and energized by each cylinder portcrossing its associated bridge, for a clockwise direction of rotation ofthe cylinder barrel on the flat valve, and vice versa for the oppositedirection of rotation of the cylinder barrel.

The cylinder ports are odd in number, and therefore when one cylinderport is centered on a bridge, the other bridge has one cylinder portentering and another leaving the bridge, such that only one of thebridge motors or auxiliary motors are directly connected to a cylinderport at one time.

In order that both bridge motors 47, 48 will he simultaneously energizedand simultaneously de-energized by a cylinder port crossing eitherbridge, means are provided for interconnecting the cylinders 44, of theauxiliary holdup motors 4'7, 48. Such interconnecting means comprises aring or sleeve fitted to the fiat valve 33 to cooperate therewith toprovide a circumferent-ially extending passage 5'6 that interconnectsdrilled passages 57, 58 which extend generally radially from the bridgecylinders 49, 50, respectively. FIGS. 3 and 4 show the sleeve 55 fittedin a counterbore in the fiat valve 33 and show that thecircumferentially extending passage 56 is formed by an annular groove inthe wall of the counterbore which is enclosed by the sleeve 55.Interconnection of the bridge motors results in both bridge motors beingsimultaneously energized when a cylinder port is in overlyingcommunication with one bridge hole 53 or 54 and the pressure port 31 andresults in both bridge motors being simultaneously deenergized when acylinder port is in overlying communication with one bridge hole 53 or54 and the exhaust port 32.

PEG. 7 shows a modification of the arrangement of FIGS. 2, 3, and 4 inwhich a ring 60- is fitted over the radially outer cylindrical surfaceof a flat valve 33a. A ciroumferentially extending passage is providedby an annular groove 61 in one of the abutting surfaces of the ring andflat valve and as shown the groove 61 is preferably provided in thecylindrical surface of the flat valve. Generally radially drilled holes62, 63 connect the bridge cylinders 49, 50, respectively, to the annulargroove 61 to thereby interconnect the bridge cylinders 4), 50. Thefunction and operation of flat valve 33a is the same as that of flatvalve 33.

While but one embodiment and one modification of the invention has beenshown and described, changes may be made therein within the scope of theappended claims.

I claim:

1. In a hydraulic machine comprising a rotatable cylinder unit having acoaxial end face having an odd number of circumferentially spacedcylinder ports and a stationary end head having an annular face coaxialwith said cylinder uni-t, an annular flat valve adapted to benon-rotatably supported on said end head for axial movement relativethereto for sealing engagement with said end face of said cylinder unit,said fiat valve having diametrically opposite arcuate supply and exhaustports with which said cylinder ports alternately register upon rotationof said cylinder unit, hydraulic hold-up motors under the ports of thefiat valve to urge the flat valve toward the cylinder unit, auxiliaryhydraulic hold-up motors in opposite segments of the fiat valve betweenthe ports thereof, axial passages in the segments of the flat valveconnecting the auxiliary hold-up motors to the face of the segment forsuccessive registration with the cylinder ports crossing the face of thesegment upon rotation of the cylinder unit, an annular member secured tosaid flat valve a circumierentially extending passage formed in one ofthe abutting surfaces of said annular member and flat valve, andconnecting passages in said flat valve connecting said auxiliary holdupmotors in both segments to said circumferentially extending passage.

2. In a hydraulic machine as defined in claim 1 in which rthe flat valvehas the annular member fitted on a cylindrical surface of the flat valveand encloses the circumfierentially extending passage therebetween, andthe connecting passages thereto extending generally radially from saidauxiliary iholdaup motors.

3. In a hydraulic machine as defined in claim 1 in which the flat valvecooperates with the annular member in providing the circumferentiallyextending passage, said fiat valve having a coaxial bore and an annulargroove the wall of said bore, said annular member defined by a sleevefitted in said bore to enclose said annular groove and define saidcircumferentially extending passage, and the connecting passages theretoextending generally radiallly from said auxiliary hold-up motors.

4. A flat valve having a front face for seating on an end of arelatively rotatable cylinder unit having an uneven number of cylinderports, said flat valve having diametrically [opposite arcuate ports withwhich said :cylinder ports are adapted to alternately register, theradial segments of said flat valve between said arcuate ports halvingbridge cylinders formed in a back face of the flat valve connected byaxial passages to the front face of the flat valve for communicationwith cylinder ports crossing the segrnents of the flat valve, a sleevefitted to a cylindrical surface of said fiat valve to enclose an annulargroove therein, and generally radially extending passages in saidsegments connecting said annular groove to said bridge cylinders.

Ferris et 211.. Aug. 20, 1946 Douglas June 5, 1962

1. IN A HYDRAULIC MACHINE COMPRISING A ROTATABLE CYLINDER UNIT HAVING ACOAXIAL END FACE HAVING AN ODD NUMBER OF CIRCUMFERENTIALLY SPACEDCYLINDER PORTS AND A STATIONARY END HEAD HAVING AN ANNULAR FACE COXIALWITH SAID CYLINDER UNIT, AN ANNULAR FLAT VALVE ADAPTED TO BENON-ROTATABLY SUPPORTED ON SAID END HEAD FOR AXIAL MOVEMENT RELATIVETHERETO FOR SEALING ENGAGEMENT WITH SAID END FACE OF SAID CYLINDER UNIT,SAID FLAT VALVE HAVING DIAMETRICALLY OPPOSITE ARCUATE SUPPLY AND EXHAUSTPORTS WITH WHICH SAID CYLINDER PORTS ALTERNATELY REGISTER UPON ROTATIONOF SAID CYLINDER UNIT, HYDRAULIC HOLD-UP MOTORS UNDER THE PORTS OF THEFLAT VALVE TO URGE THE FLAT VALVE TOWARD THE CYLINDER UNIT, AUXILLARYHYDRAULIC HOLD-UP MOTORS IN OPPOSITE SEGMENTS OF THE FLAT VALVE BETWEENTHE PORTS THEREOF, AXIAL PASSAGES IN THE SEGMENTS OF THE FLAT VALVECONNECTING THE AUXILLARY HOLD-UP MOTORS TO THE FACE OF THE SEGMENT FORSUCCESSIVE REGISTRATION WITH THE CYLINDER PORTS CROSSING THE FACE OF THESEGMENT UPON ROTATION OF THE CYLINDER UNIT, AN ANNULAR MEMBER SECURED TOSAID FLAT VALVE A CIRCUMFERENTIALLY EXTENDING PASSAGE FORMED IN ONE OFTHE ABUTTING SURFACES OF SAID ANNULAR MEMBER AND FLAT VALVE, ANDCONNECTING PASSAGES IN SAID FLAT VALVE CONNECTING SAID AUXILIARY HOLDUPMOTORS IN BOTH SEGMENTS TO SAID CIRCUMFERENTIALLY EXTENDING PASSAGE.